To detect new cells, a long term evolution (LTE) handset, i.e. a user equipment (UE), must perform cell search procedures. Cell search is used to gain time and frequency synchronization to the LTE base station, i.e. the evolved Node B (eNode B, eNB), and acquire system parameters such as the cell ID, duplex mode, and cyclic prefix length. eNBs, for example, broadcast Primary Synchronization Signals (PSSs) and Secondary Synchronization Signals (SSSs) to facilitate initial establishment of time and frequency synchronization in addition to cell-specific reference signals (CRSs) for time and frequency synchronization tracking. In other to achieve optimal system performance and to minimize coverage outage, the cell searching mechanism has to reliably detect new cells in low signal-to-interference-plus-noise ratio (SINR) conditions to facilitate re-selection and handover at the cell edge.
The concept of heterogeneous networks has been prevalent in the Third Generation Partnership Project (3GPP) Release 10 and subsequent releases. Heterogeneous networks deploy an overlay of small cells, e.g. picocells, with limited coverage within macro cells, e.g. LTE cells, to provide additional capacity and/or coverage to the overall network. To suppress the interference in a heterogeneous network, the concept of Enhanced-Inter-Cell-Interference. Coordination (eICIC) is introduced through the implementation of Almost Blank Subframes (ABS). However, in order to support Release 8 and 9 compliant devices, synchronization and physical broadcast channel (PBCH) signals are not suppressed and therefore must be decoded in hostile interference scenarios.